Sahih Muslim
The Book of Prayers (Kitab Al-Salat)
Book Number: 004 / Hadith Number: 1457
Qatada reported it on the authority of Anas b. Malik that the Messenger of Allah (may peace be upon him) said: When any one of you omits the prayer due to sleep or he forgets it, he should observe it when he remembers it, for Allah has said:" Observe prayer for remembrance of Me."